1. Field of the Invention
The present invention relates to nuclear reactor vessels, and in particular to a system that may be used to simplify and facilitate the installation, removal and/or replacement of a component of a nuclear reactor vessel such as a control rod drive mechanism (CRDM).
2. Related Art
In a Boiling Water Reactor (BWR) type nuclear reactor, a number of control rods are provided within the reactor vessel, each control rod being positioned between a number of (e.g., four) nuclear fuel bundles. The power output of a BWR is controlled by the elevation position of the control rods within the fuel bundles. The position of each control rod is controlled by a control rod drive mechanisms (CRDM), which selectively raises and lowers the control rod within the BWR vessel.
Some components, such as seals, of a CRDM wear over time. It is thus necessary from time to time to replace one or more CRDMs in a BWR vessel. However, not all BWR power plants are designed and configured in the same manner. Thus, there is a need for an system that simplifies and facilitates the installation, removal and/or replacement of CRDMs or other components in nuclear reactor vessels such as BWRs that has the flexibility to accommodate for different power plant designs and configurations.